Tuesday, July 8, 2008

ISA HK/China --- 2008 Research on Containerized Tree Planting

*** Our weekly Station Mail is for the information of Station Members only, but Station Mail has given up copyright & can be freely circulated. For administrative reasons, comments from outsiders are usually not entertained & may be circulated within our system locally & overseas. Please note Station Mail is sometimes given in Blog at http://isahkchina.blogspot.com/ , although images are usually not attached due to size. ***

Dear Station Members,

Containerized Trees are frequently used in our territory especially in places where ground planting is not possible, e.g. podium & shopping mall. Rooftop tree planting is in a way a form of Containerized Tree Planting since soil is confined to man-made planters without connection to ground, & is subject to ambient temperature variation & artificial water replenishment during dry season . Ficus benjamina, a fast & tough growing species is a favourable choice for this purpose, usually without much consideration of its natural habitat & wind loading ability.

Drought tolerance in selecting Containerized Trees does not always appear to be a prime consideration in our territory, since it would be the contractors getting the blame if the trees do not perform well. Some of the contract conditions in our territory would prime to facilitate administration & management rather than the conveniences of the workers doing it. Therefore resentment would grow among contractors, which in turn would slow the work & harm the harmony between the parties involved.

HK is a place where summer heat & winter drought are major concern for sustainable landscape. Containerized Planting has become a major challenge for our landscapers. Coupling with typhoons in the summer season, making Containerized Trees a success is no easy task. On the other hand, forcing through realities for a moment of visual pleasure would usually lead to over-burden in maintenance, & may be even eventual tree failure in wind & drought. It therefore has to be a careful choice indeed.

Attached is the latest research from ISA to provide information on the challenges of using Containerized Trees in open areas. Water management appeared to be a major concern with species demand & environmental consideration. We Arborists have a famous saying that: Mother Nature makes the rules, not any of us. If the wrong tree is planted in the wrong place, sustainability is always in doubt when maintenance has become inconvenient or impractical.

Arboriculture is a scientific discipline & Arborists believe in facts & research. Lets hope the article attached can throw some light to our profession & help our people who have to deal with Containerized Tree planting under our conditions.

best regards,

Sammy Au
Station Manager

The ISA Mission - Through research, technology, and education, promote the professional practice of arboriculture and foster a greater public awareness of the benefits of trees. (http://www.isa-arbor.com/)